This month, many of the 80 million owners of Roku devices, including streaming sticks, set-top boxes and internet-connected TVs running the company’s streaming software, turned on their Rokus to see a block of text. I, the owner of a cheap Roku TV in my bedroom, was among those who got stuck with the screen.

The message gave updated terms of service that made it harder for customers to take legal action against the company. Unless they agreed, users were blocked from access to the Roku menu and apps, essentially bricking their devices. The only way to opt out was to mail a letter to the company.

To Isaac Phillips, a software engineer in Tampa, Fla., this felt unfair. So he came up with a workaround to disconnect his Roku TV from the internet and use it as a normal TV without Roku’s apps, which include Netflix, Hulu and other streaming services.

“It should belong to whoever paid for it,” Mr. Phillips said. “To lock somebody out of it completely just doesn’t seem right. It’s pretty unacceptable.”

Also this month, Roku announced a security breach involving about 15,000 user accounts. The victims’ login credentials had been illegally obtained through a breach of another company’s servers and were used to get into Roku accounts to buy streaming subscriptions, according to Roku.

“Like many companies, Roku updates its terms of service from time to time,” the company said in a statement, adding that the change was unrelated to the breach.